Bio Hw due 9/22 Flashcards
Theodor Schwamn extended Schleidan’s hypothesis by suggesting that animal tissue was made of:
cells
NOT a part of the cell theory
All cells are repalced
Most important factor that limits the size of cells?
Diffusion of substances in and out of the cell
NOT a variable that affects the rate of diffusion through cell plasma
The volume of the cell
If the radius of the cell increases by 10 times, then the surface area will increase by ____ times and the voume will increase by ______ times.
100,1000
The purpose of a compound light microscope can best described as
to allow the visualization of cells and cellular componets
The limitation of resolution for the human eye
100 micrometers
A measure of clarity is the ability to observe 2 adjacent objects as distinct from one another:
Resolution
Although resolution remains a physical limit we can improve the contrast between different cellular componets by:
Applying chemical stains to cells
Technique involving the use of stains that bind to specific types of molecules by using antibodies
immunohistochemistry
Are the cellular structure that all cells need to synthesize proteins
ribosomes
Contain their genetic material in a nucleoid region
Prokaryotes
Region of the cell contained with in plasma membrane
Cytoplasm
Describes an organelle
A membrane component with its own unique structure and function
Most cells cannot be seen without a microscope why?
Because of the limited resolving power of the human eye
Structures ONLY found in prokaryotic cells
Nucleoid
Pili
Groups of organisms have prokaryotic cells
Archaea and Bacteria
Structures called ____ are found in both prokaryotic and eukaryotic cells and are the sites of polypeptide synthesis.
ribosomes
TRUE OR FALSE:
Prokaryotes lack cytoskeletal elements?
False
Most bacterial cells are encased by a strong cell wall composed of ______ which is a carbohydrate matrix cross linked by polypeptides.
peptidoglycan
The ____ _______ of a bacterium helps the organism maintain its shape and prevents the excessive loss of water.
cell wall
When certain bacteria produce protective polysaccharide capsules, disease causing bacteria use these capsules to aid in:
adhering to surfaces
Common to bacteria and archaea ?
Ribosomes
a plasma membrane
Antibiotics such as penicillin and vancomyicin interefere with
peptidoglycan synthesis
Archaea differ from bacteria in which of the following ways?
They lack peptidoglycan
Thermal protection in archaea relates to which of the following?
Saturated hydrocarbons in a monolayer
Archaea appear to be mostly related to:
Eukaryotes
Long thread like structures protruding from the surface of prokaryotic cells that are used for locomotion
Flagella
What property do flagella provide to bacterial cells?
Motility
Who was the natural philosopher that studied cork cells under a compound microscope in 1665?
Hooke
The surface of the nucleus is bounded by 2 phospholipid bilayer membranes, collectively called the_____ envelope
nuclear
Problems faced by larger cells compared to smaller cells
- They need to produce more macromolecules
- -Greater production of wastes
- Higher energy requirements
Macroscopic cells
vertebrate eggs
A compound microscope can resolve structures that are how far apart?
200 nm or greater.
A light microscope utilizes _____ for illumination whereas an electron microscope uses a beam of ______.
light, electrons
With TEM, a beam of ____ is transmitted through a biological sample.
electrons
The plasma ______ is a phospholipid bilayer that forms a barrier between cell and its external enviroment.
membrane
_____ transport essential nutrients and ions into the cell and export susbstances out of the cell
Proteins
Nuclear _____ form at the points where the inner and outer nuclear membrane meet.
pores
Types of molecules that can move through the nuclear enevelope:
ions
RNA
The inner surface of the nuclear envelope us covered with a network of fibers called
Nuclear Lamina
Chromatin must be compacted into a more highly condensed state during ____ ______
cell division
Before cells can synthesize proteins in large quanitity they must first construct a large number of ______ to carry out this synthesis
ribosomes
Genes encoding ribomosal RNAs are often clustered together on the chromosome, facilitating the construction of ribosomes. How many copies of those genes are found on the chromosome?
Hundreds
Ribosomal subunits are produced ina region of the nucleus called ?
Nucleoli
Ribosomes are responsible for _____ synthesis in the cell
protein
2 subunits make up a ____
ribosome
_______ type of RNA carries information form DNA
messenger
The _____ may be called the “universal organelle” because it is found in prokaryotes and eukaryotes.
ribosomes
